<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="../react18/react.development.js"></script>
    <script src="../react18/react-dom.development.js"></script>
    <script src="../react18/babel.min.js"></script>
    <script src="../react18/prop-types.js"></script>
</head>

<body>
    <div id="app"></div>
    <script type="text/babel">
        /*
        当表单的value收state控制时,则我们称作为受控表单
         -受控表单的三种用法:
          1,表单的初始值受控直接写defaultValue属性
          2,表单是,只读表单(设置了readyOnly={true}),直接设置value也可以
          3,数据的双向绑定,表单通过value受控,然后要绑定onChange事件,事件中获取当前表单的值修改state

        情况2有警告:
        Warning: You provided a `value` prop to a form field without an `onChange` handler. This will render a read-only field. If the field should be mutable use `defaultValue`. Otherwise, set either `onChange` or `readOnly`.
        */
        class App extends React.Component {
            state = {
                name: "laowang",
                age: 18,
                hobby: "吃饭"
            }
            render() {
                const { name, age, hobby } = this.state
                return (
                    <div>
                        姓名: <input type="text" defaultValue={name} />
                        <br />
                        年龄: <input type="text" value={age} />
                        <br />
                        爱好: <input type="text" value={hobby} />
                        <br />
                        <button onClick={this.handle}>提交</button>
                    </div>
                )
            }

            handle = () => {

            }
        }

        const root = ReactDOM.createRoot(document.getElementById('app'));
        root.render(<App />)


    </script>
</body>

</html>